[flang-commits] [flang] 7a48740 - [Flang] Fix statement-function shadowing to avoid false unresolved-symbol internal error (#189360)

[via flang-commits]

Author: CHANDRA GHALE
Date: 2026-04-15T18:41:49+05:30
New Revision: 7a48740f3c122a9e45172f609ef22335962248e3

URL: https://github.com/llvm/llvm-project/commit/7a48740f3c122a9e45172f609ef22335962248e3
DIFF: https://github.com/llvm/llvm-project/commit/7a48740f3c122a9e45172f609ef22335962248e3.diff

LOG: [Flang] Fix statement-function shadowing to avoid false unresolved-symbol internal error (#189360)

When a statement function shadows a host-associated internal procedure
name, HandleStmtFunction creates a local symbol but leaves name.symbol
pointing to the host SubprogramNameDetails.

Because of that stale pointer, AnalyzeStmtFunctionStmt exits early (it
expects SubprogramDetails), so the RHS is never resolved and flang emits
a false `internal error: "Internal: no symbol found".` Clearing
name.symbol after creating the local shadow symbol lets it re-resolve
correctly and fixes the issue.

---------

Co-authored-by: Chandra Ghale <ghale at pe34genoa.hpc.amslabs.hpecorp.net>

Added: 
    flang/test/Semantics/stmt-func03.f90

Modified: 
    flang/lib/Semantics/resolve-names.cpp
    flang/test/Semantics/stmt-func02.f90

Removed: 
    


################################################################################
diff  --git a/flang/lib/Semantics/resolve-names.cpp b/flang/lib/Semantics/resolve-names.cpp
index b6907cc792d76..a554174b7d30a 100644
--- a/flang/lib/Semantics/resolve-names.cpp
+++ b/flang/lib/Semantics/resolve-names.cpp
@@ -4687,6 +4687,10 @@ bool SubprogramVisitor::HandleStmtFunction(const parser::StmtFunctionStmt &x) {
           "Name '%s' from host scope should have a type declaration before its local statement function definition"_port_en_US,
           name.source);
       MakeSymbol(name, Attrs{}, UnknownDetails{});
+      // 'name' may still point to a host-associated SubprogramNameDetails
+      // symbol. Reset it so statement-function processing
+      // re-resolves to the new local SubprogramDetails.
+      name.symbol = nullptr;
     } else if (auto *entity{ultimate.detailsIf<EntityDetails>()};
                entity && !ultimate.has<ProcEntityDetails>()) {
       resultType = entity->type();

diff  --git a/flang/test/Semantics/stmt-func02.f90 b/flang/test/Semantics/stmt-func02.f90
index 10166a0abf7b1..d2c408b4dbb82 100644
--- a/flang/test/Semantics/stmt-func02.f90
+++ b/flang/test/Semantics/stmt-func02.f90
@@ -25,10 +25,12 @@ subroutine test1
   end
   subroutine test2
     !PORTABILITY: Name 'rf' from host scope should have a type declaration before its local statement function definition [-Wstatement-function-extensions]
+    !PORTABILITY: An implicitly typed statement function should not appear when the same symbol is available in its host scope [-Wstatement-function-extensions]
     rf(x) = 1.
   end
   subroutine test2b
     !PORTABILITY: Name 'rf2' from host scope should have a type declaration before its local statement function definition [-Wstatement-function-extensions]
+    !PORTABILITY: An implicitly typed statement function should not appear when the same symbol is available in its host scope [-Wstatement-function-extensions]
     rf2(x) = 1.
   end
   subroutine test3

diff  --git a/flang/test/Semantics/stmt-func03.f90 b/flang/test/Semantics/stmt-func03.f90
new file mode 100644
index 0000000000000..111a6111f720a
--- /dev/null
+++ b/flang/test/Semantics/stmt-func03.f90
@@ -0,0 +1,18 @@
+! RUN: %flang_fc1 -fsyntax-only -pedantic %s 2>&1 | FileCheck %s
+! CHECK-NOT: error:
+! CHECK-NOT: Internal:
+program main
+contains
+  subroutine internal_sub()
+    integer :: i, result
+    ! Host-associated sibling internal function name should be shadowed
+    ! by this statement function definition.
+    stmt_function(i) = i * 2
+    i = 1
+    result = stmt_function(i)
+  end subroutine internal_sub
+  integer function stmt_function(arg)
+    integer :: arg
+    stmt_function = arg * 3
+  end function stmt_function
+end program main